A trolley with a hanger plate to convey a hung article, travelling along the horizontal track on the lower protrusion of a crossbeam such as an I-shaped beam, comprises two side plates coupled by a stay rod which suspends a hanger plate.
Each of said side plates supports face to face a pair of rollers which run on the track. The space between the side plates is adjustable so that the trolley can be used on I-beams which may vary in size. A hanger plate must be coupled to the stay rod exactly midway between both the side plates to balance the load on the two tracks of an I-beam each time said adjustment is applied.
Assemblage and the above described spacing adjustment of the side plates of the known and customary trolleys always require tools for tightening and loosening the bolts and nuts which are used to fix the stay rod inserted in the bushes mounted on the side plates.
Unless such tools are provided on the spot, however, assemblage of a trolley and its engagement with a rail are impossible. Furthermore, spacing adjustment of the side plates and positioning of the hanger plate on the stay rod are not easy to do.